Best AI Prompts for Summarizing Long Documents
Updated 2026-08-06 \u00b7 4 min read
TL;DR
The best summarization prompts specify length, audience, and what to prioritize, since a generic summarize this request produces inconsistent results on long documents.
The basic reliable structure
State the target length, the intended audience, and ask for the summary to preserve key numbers, decisions, or action items specifically.
For very long documents
Break the document into sections and summarize each before asking for a combined summary, since single-pass summaries of very long text tend to drop details.
Extracting action items separately
Ask for a separate list of action items or decisions after the summary, rather than mixed in, so nothing gets buried in prose.
Related reading
These prompts work best alongside the fundamentals in the prompt engineering guide.
Frequently asked questions
Why does the AI skip important details in long documents?
Very long inputs can dilute attention across the text. Breaking it into sections before summarizing usually fixes this.
Can I ask for different summary lengths for different audiences?
Yes, specifying the audience and length explicitly is the single biggest lever for a useful summary.
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